Question: Cystic Fibrosis Mr. And Mrs. Frank Are Planning To Conceive A Child And Are Interested In Receiving Genetic Counseling Because Of Their Ages And A History Of Cystic Fibrosis On Mrs. Frank’s Side Of The Family. A Brief History Reveals That Mr. Frank Has No Known Family History Of Cystic Fibrosis Or Any Other Genetic Disorder. He Is 45 Yo And Has 2 Children …

Cystic Fibrosis Mr. and Mrs. Frank are planning to conceive a child and are interested in receiving genetic counseling because of their ages and a history of cystic fibrosis on Mrs. Frank’s side of the family. A brief history reveals that Mr. Frank has no known family history of cystic fibrosis or any other genetic disorder. He is 45 yo and has 2 children from a previous marriage, both of whom are well. Mrs. Frank has a sister with three children, the last of whom was diagnosed with cystic fibrosis. There are no other known family members with the disease. Mrs. Frank is 35 yo and has no children. 1. When assess the risk factor for bearing a child with cystic fibrosis one must consider that the disease is genetically inherited as a. Autosomal dominant b. Autosomal recessive c. X-linked d. Chromosomal 2. Assuming the worst-case scenario, which is that both Mr. and Mrs. Frank have the defective gene for cystic fibrosis, what is the probability of their having an affected child? a. No risk b. 50% c. 25% d. 75% 3. After genetic testing Mr. Frank does not have the CF gene. Mrs. Frank is heterozygous (one normal gene, one cystic fibrosis gene. What is the child’s risk of being affected by CF? a. Near 0% b. 50% c. 25% d. 75%